1. Field of the Invention
The present invention relates to a method for manufacturing an ink jet recording head used in a recording apparatus that performs a recording operation by discharging ink or the like.
2. Description of the Related Art
Ink jet recording apparatuses (hereinafter, referred to as “recording apparatus”) as one type of a recording apparatus are broadly used for an output apparatus connected to a computer and the like and are commercialized. Recently, in order to perform high image-quality recording at higher speed, an ink jet recording head (hereinafter, referred to as a “recording head”) having a longer recording width is desirable.
As a general recording apparatus, there is widely known a type in which a recording head having discharge ports used for discharging ink performs recording by scanning a recording medium such as a paper sheet while discharging ink. In addition, in the case of a head having a long recording width, there is also known a recording apparatus that can perform recording at high speed by fixing a recording medium on a conveying belt and scanning the recording medium.
In order to configure the recording head having a long recording width as above by using one recording element substrate, the recording element substrate needs to be formed to be long. However, in such a case, there is a very high likelihood that defective products are produced. This leads to a decrease in a yield of the recording element substrate and the like. Accordingly, a configuration is considered in which a recording head having a long recording width as a whole is realized by arranging a plurality of recording element substrates having an appropriate length (that is, an appropriate number of nozzles) on a support substrate having a length that is equal to or greater than the recording width.
However, when the support substrate is formed to be long, a warped state or undulation of the support substrate may occur. When the recording element substrates are fixed along the support substrate surface, the ink discharging direction is changed for each recording element substrate, whereby the precision of landing of ink decreases. In addition, when there is a variation in the thicknesses of the recording element substrates, a distance from a discharge port to a recording medium varies depending on each recording element substrate, whereby the precision of landing of ink decreases.
Thus, in Japanese Patent Application Laid-Open No. 2006-256051, a configuration is proposed in which surfaces forming ink discharge ports of the recording element substrates are made flush with each other by variation of the thickness of an adhesive that bonds a support substrate and the recording element substrate for each recording element substrate. In FIG. 3A of Japanese Patent Application Laid-Open No. 2006-256051, recording head units (recording element substrates) are bonded and fixed to a long substrate (support substrate) with the adhesive. Even when a warped state of the long substrate occurs or there is a variation in the thicknesses of the recording head units, the discharge port forming surfaces are made flush with each other by changing the thickness of the adhesive beneath each recording head unit.
However, in the above-described technique, there are the following problems.
In the method disclosed in Japanese Patent Application Laid-Open No. 2006-256051, in a case where an electricity-heat transducing element is used as an element that generates energy used for discharging ink, when the heat generated for discharging the ink conducts the support substrate, heat conduction differs depending on a difference in the thickness of the adhesive for each recording element substrate. In other words, the heat dissipating characteristics are different for each recording element substrate. As a result, the amount of discharged ink or the discharge speed of ink differs for each recording element substrate, whereby the recording quality is lowered.